Wound pad and a self-adhesive member comprising a wound pad

ABSTRACT

Described is a wound pad having a liquid retaining layer, and a distributing layer, wherein the liquid retaining layer, or the distributing layer, or both the liquid retaining layer and the distributing layer includes fibers and being provided with at least a first and a second discrete group of incisions, wherein the first and second discrete groups of incisions each includes a first incision extending from a starting point to a respective end point, and wherein the first incision extends though the liquid retaining layer, or the distributing layer, or both the liquid retaining layer and the distributing layer.

FIELD OF THE INVENTION

The present invention relates to a wound pad comprising fibers and beingprovided with at least a first and a second discrete group of incisions,wherein each one of said discrete groups of incisions comprises at leasta first and a second incision.

It also relates to a self-adhesive member for adhering to and covering aportion of a user’s skin, said self-adhesive member comprising a woundcontact layer having a self-adhesive coating and a wound pad.

TECHNICAL BACKGROUND

Self-adhesive wound care products or dressings are frequently used inwound care. Such wound care products typically include a wound contactlayer having an adhesive coating and a wound pad.

For wound care products, wear time is an important factor. Adhesivewound care products often have a tendency to start losing the adhesiveconnection with the user’s skin along the edges of the wound careproduct, due to e.g. friction between the adhesive dressing andmaterials, such as clothes or bed clothing, that the adhesive dressingcontact during normal use of it or because of movements of the userwearing the dressing, e.g. by bending of a knee or arm. This is ofcourse undesired, since it may lead to the wound care product beinguncomfortable to wear, and to lost function of the product as it may notcover the wound properly. However, there is also a constant strivetowards using mild adhesives for the wound care products, as that ismore friendly to the user’s skin. These two needs must be balanced inorder to achieve a product that is both reliable and user-friendly.

Hence, there is a need for a self-adhesive wound care product that hasimproved wear time.

SUMMARY OF THE INVENTION

The present invention solves the above-identified and other problems byproviding a wound pad comprising fibers having discrete groups ofincisions. The discrete groups of incisions are provided with an overlapsuch that an incision of a group of incisions has its starting point onone side of an imaginary line extending in the machine direction of thewound pad and intersects that imaginary line, wherein an incision ofanother group of incisions has its starting point on the other side ofsaid imaginary line, and wherein that incision also intersects saidimaginary line. Depending on the amount of groups of incisions and theirpositions, all or some of the fibers of the wound pad will be cut alongtheir extension, and the wound pad thereby becomes more flexible. With amore flexible wound pad, the wound pad may easier conform to the user’sbody and less stress is applied to the wound pad during use. Thereby, amore skin friendly adhesive may be used.

According to a first aspect of the present invention, a wound padcomprising fibers and being provided with at least a first and a seconddiscrete group of incisions is provided. Each one of said discretegroups of incisions comprises at least a first and a second incision,wherein said first and said second incision extend from a commonstarting point to a respective end point, wherein the end point of saidfirst incision is spaced from the end point of said second incision,wherein the common starting point of said first group of incisions isprovided on a first side of an imaginary line extending in the machinedirection of said fibrous wound pad, and the common starting point ofsaid second group of incisions is provided on a second side of saidimaginary line, and wherein a first incision of said first group ofincisions and a second incision of said second group of incisions eachcross said imaginary line.

A wound pad according to this first aspect fulfills the needs of a woundpad in terms of fluid handling capacity at the same time as it becomesmore flexible than previously known wound pads.

That each group of incisions comprises at least two incisions isintended to mean that it has at least two straight or curved cuts in aplane of the wound pad, wherein the plane is substantially parallel tothe plane of an outer wound contact surface of the wound pad. The depthsof the incisions thereby extend in a plane being perpendicular to theouter wound contact surface of the wound pad.

However, the at least two incisions may well be made by only one tool,such as a cutting tool having a plurality of blades. Hence, according toan exemplary embodiment, said incisions are made by a cutting tool suchas a knife. According to another exemplary embodiment, said incisionsare made by cutting by laser.

The term machine direction defines the lengthwise direction of thematerial web during production. Hence, before the products are being cutfrom the roll, the machine direction defines the length of the roll. Theterm cross-direction defines a direction being perpendicular to themachine direction.

With the provision of incisions in the manner described above, i.e. thatthe common starting point of said first group of incisions is providedon a first side of an imaginary line extending in the machine directionof said fibrous wound pad, and the common starting point of said secondgroup of incisions is provided on a second side of said imaginary line,and wherein a first incision of said first group of incisions and asecond incision of said second group of incisions each cross saidimaginary line, one of the incisions of the first group of incisionswill overlap one of the incisions of the second group of incisions.Hence, with overlap is in this application not meant that the incisionsmust intersect each other, but that their extension is such that theyboth intersect the same imaginary straight line extending in the machinedirection of the wound pad. By this, fibers present in any of the layersof the wound pad, in an area where groups of incisions are provided,will be cut at least once along their extension. A straight line drawnin the machine direction of the wound pad, and in the area of the woundpad where the groups of incisions are provided, will thereby always passat least one incisions, and potentially also pass several incisions fromdifferent groups of incisions.

The total fluid handling capacity is also increased and especially themoisture vapour loss is largely increased with the inventive dressing.This can be attributed to the increased product flexibility provided bythe group of incisions. The wound pad is allowed to stretch in alldirections during wet conditions. Therefore, the movement and spreadingof liquid within the dressing is improved, and excess liquid canevaporate from the product, and be transferred out from the wound padthrough the backing layer. In other words, the dressing does not becomesaturated as quickly, and the dressing can be left in place for a longertime compared to a non-flexible product according to the prior art.

According to another exemplary embodiment, the overlap of two incisionsmay be described in that said groups of incisions are provided such thata first imaginary tetragon circumscribing a first group of incisionswill partially cross a second imaginary tetragon circumscribing a secondgroup of incisions, wherein the imaginary tetragons have two sidesextending in the machine direction of the wound pad and two sidesextending in the cross-direction of the wound pad, and wherein eachtetragon is the smallest possible tetragon circumscribing a group ofincisions.

According to another exemplary embodiment, the overlap of two incisionsmay be described in that said groups of incisions are provided such thata first imaginary tetragon circumscribing a first group of incisionswill partially cross a second imaginary tetragon circumscribing a secondgroup of incisions, wherein the imaginary tetragons have two sidesextending in the machine direction of the wound pad and two sidesextending in the cross-direction of the wound pad, and wherein eachtetragon is provided such that the centre of at least one of the sidesof it is in contact with the end point of one of the incisions.

According to one exemplary embodiment, in which each group of incisionscomprises three incisions, the tetragon is provided such that a firstone of its corners is provided at the end point of a first incision, asecond one of its corners is provided at the end point of a secondincision, and a centre of one of its sides is provided at an end point athird incision.

According to one exemplary embodiment, in which each group of incisionscomprises four incisions being provided orthogonally to each other, thetetragon is provided such that a respective centre of each one of thesides is provided at an end point of a respective incision.

According to an exemplary embodiment, there is an overlap, according tothe definition given above, between the incisions of a first group ofincisions with at least two other groups of incisions. It is accordingto this embodiment not necessary that it is the same incision of thefirst group of incisions that overlap both two other groups ofincisions, it may also be that the first incision of the first group ofincisions overlap an incision of a second group of incisions and thesecond incision of the first group of incisions overlap an incision of athird group of incisions.

According to an exemplary embodiment, there is an overlap between one orseveral of the incisions of a first group of incisions with one orseveral incisions of at least three other groups of incisions. It is,similar to the previous exemplary embodiment, not necessary that it isthe same incision of the first group of incisions that overlap incisionsof the three other groups of incisions.

According to an exemplary embodiment, there is an overlap between theincisions of a first group of incisions with the incisions of at leastfour other groups of incisions. It is, similar to the two previousembodiments, not necessary that it is the same incision of the firstgroup of incisions that overlap the incisions of the four other groupsof incisions.

According to an exemplary embodiment, the common starting point of saidfirst group of incisions is also provided on a first side of animaginary line extending in the cross direction of said fibrous woundpad, and the common starting point of said second group of incisions isprovided on a second side of said imaginary line, and wherein a firstincision of said first group of incisions and a second incision of saidsecond group of incisions each cross said imaginary line. Hence,according to this embodiment, overlapping incisions, according to thedefinition of overlap in this application, are provided in both themachine direction and the cross direction of the wound pad.

According to an exemplary embodiment, the common starting point of saidfirst group of incisions is also provided on a first side of animaginary line extending in a diagonal direction of said fibrous woundpad, and the common starting point of said second group of incisions isprovided on a second side of said imaginary line, and wherein a firstincision of said first group of incisions and a second incision of saidsecond group of incisions each cross said imaginary line. With diagonaldirection is meant a direction having an angle of 45° in relation to themachine direction of the wound pad. Hence, according to this embodiment,overlapping incisions, according to the definition of overlap in thisapplication, are provided in both the machine direction and the diagonaldirection of the wound pad. It is also conceivable with an embodiment inwhich overlaps are provided in the machine direction, the crossdirection and the diagonal direction of the wound pad.

According to an exemplary embodiment, the common starting point of saidfirst group of incisions is also provided on a first side of animaginary straight line extending in any direction, from a firstperipheral point of said fibrous wound pad to a second peripheral pointof said fibrous wound pad, and the common starting point of said secondgroup of incisions is provided on a second side of said imaginary line,and wherein a first incision of said first group of incisions and asecond incision of said second group of incisions each cross saidimaginary line.

According to an exemplary embodiment, there is at least 1 mm between theincisions of a first group of incisions and the incisions of the othergroups of incisions. Hence, according to this exemplary embodiment, theincisions overlapping each other are provided at least 1 mm from eachother. By this, a sufficient amount of material is provided between eachdiscrete group of incision so that the wound pad can absorb andtransport the required amount of wound fluids. The amount of materialaround each discrete group of incisions also provides for a suitablestability of the wound pad.

According to an exemplary embodiment, said incisions extend through theentire thickness of the wound pad. According to another exemplaryembodiment, said incisions do not extend through the entire thickness ofthe wound pad. Wound pads may be configured with different number oflayers comprising different kinds of materials, depending on theintended usage of the wound pad. For certain embodiments it may bebeneficial if the incisions extend through the entire thickness of thewound pad, while it for others may be beneficial if they only extendthrough some of the layers, or partially through a layer.

According to an exemplary embodiment, each one of said discrete groupsof incisions also comprises at least a third incision extending fromsaid common starting point.

According to an exemplary embodiment, each one of said incisions has astraight extension.

According to an exemplary embodiment, the angle between one of theincisions within a group of incisions and another incision within thesame group of incisions is between 60° and 150°.

According to another exemplary embodiment, the angle between one of theincisions within a group of incisions and another incision within thesame group of incisions is between 72° and 120°.

The angles between the incisions within each group of incisions aredependent on the number of incisions within each group. It is possible,but not necessary that the angles are the same between all incisionswithin a group of incisions.

According to an exemplary embodiment, said first incision within eachgroup of incisions extends in a direction having an angle of 60° - 90°,more preferably 75° - 90°, and most preferred 90° in relation to themachine direction of the wound pad. By providing a first incision withineach group of incisions with an angle to the machine direction of thewound pad being within the ranges according to this embodiment, thefibers of a fiber-based layer in the wound pad will be cut to asufficient degree along their extension.

According to an exemplary embodiment, the angle between said secondincision and said third incision, within the same group of incisions, isbetween 60° and 120°. The angles between the incisions within each groupof incisions are dependent on the number of incisions within each group.It is possible, but not necessary that the angles are the same betweenall incisions within a group of incisions.

According to one exemplary embodiment, in which the group of incisionsconsists of three incisions, the angle between each one of the incisionsis 120°.

According to an exemplary embodiment, the length of each one of saidincisions is between 3 and 7 mm, preferably between 4 and 6 mm and mostpreferably 5 mm.

According to an exemplary embodiment, the length of each one of theincisions within a group of incisions is the same.

According to an exemplary embodiment, each group of incisions has thesame dimensions and shape as the other groups of incisions provided onthe wound pad.

Hence, the length of the incisions within a group of incisions may bethe same, but it is not necessary. Also, the length of the incisions mayvary between different groups of incisions. However, they may also bethe same on the entire wound pad.

According to one exemplary embodiment, the distance between therespective common starting points of two adjacent groups of incisions isshorter than twice the length of each one of said incisions in theadjacent groups of incisions.

According to an exemplary embodiment, the width of each one of saidincisions is less than 1 mm. With incisions are meant cuts in which aslittle material as possible is removed. According to an exemplaryembodiment, no material at all is removed from said wound pad.

According to an exemplary embodiment, said wound pad comprises adistributing layer, comprising non-woven material.

According to an exemplary embodiment, said non-woven material comprisespolyester and/or viscose fibers.

According to one exemplary embodiment, the incisions extend through saiddistributing layer of the wound pad.

According to an exemplary embodiment, said wound pad comprises a liquidretaining and liquid transporting layer. According to an exemplaryembodiment, said liquid retaining and liquid transporting layercomprises super absorbent material.

According to an exemplary embodiment, said wound pad comprises a liquidtransporting layer. According to an exemplary embodiment, said liquidtransporting layer comprises a foam based material.

According to an exemplary embodiment, said wound pad comprises a fourthlayer. According to an exemplary embodiment, said fourth layer comprisesfoam.

The different layers of a wound pad mentioned above may be combined tomany different embodiments. According to an exemplary embodiment, saidwound pad comprises a first layer being a liquid transporting layer, asecond layer being a distributing layer, and a third layer being aliquid retaining and liquid transporting layer, wherein said liquidtransporting layer is provided on one side of said distributing layer,and said liquid retaining and liquid transporting layer is provided onthe other side of said distributing layer. Another exemplary embodimentcomprises, in addition to the previous exemplary embodiment, said fourthfoam based layer, being provided on the side of said liquid retainingand liquid transporting layer that is directed away from saiddistributing layer. Another exemplary embodiment comprises adistributing layer and a liquid retaining and liquid transporting layer.Another exemplary embodiment comprises a liquid transporting layer and adistributing layer.

According to an exemplary embodiment said incisions extend through saiddistributing layer. The distributing layer is, in many wound pads, thestiffest layer. Hence, providing said distributing layer with incisionshas the greatest effect on flexibility, as compared to cutting throughany of the other layers of a wound care product, even if it also incertain applications may be beneficial to cut trough also one or severalof the other layers. It may also in certain applications also bebeneficial to not cut through the distributing layer, and only cutthrough one or several of the other layers.

According to an exemplary embodiment, said incisions extend through bothsaid liquid retaining and liquid transporting layer and saiddistributing layer. In this embodiment, the cuts may be made by cuttingfrom the liquid retaining and liquid transporting layer side of thewound pad.

According to an exemplary embodiment, said incisions extend through saidliquid retaining and liquid transporting layer, said distributing layerand at least partially through said liquid transporting layer. In thisembodiment, the cuts may be made by cutting from the liquid retainingand liquid transporting layer side of the wound pad, but the cuts aremade somewhat deeper than in the previous exemplary embodiment andtherefore extend into the liquid transporting layer.

According to an exemplary embodiment, said incisions extend through bothsaid liquid transporting layer and said distributing layer. In thisembodiment, the cuts may be made by cutting from the liquid transportinglayer side of the wound pad.

According to an exemplary embodiment, said incisions extend through saidliquid transporting layer, said distributing layer and at leastpartially through said liquid retaining and liquid transporting layer.In this embodiment, the cuts may be made by cutting from the liquidtransporting layer side of the wound pad, but the cuts are made somewhatdeeper than in the previous exemplary embodiment and therefore extendinto the liquid retaining and liquid transporting layer.

According to an exemplary embodiment, said incisions extend through theentire wound pad. For example, if the wound pad comprises a liquidtransporting layer, a distributing layer and a liquid retaining andliquid transporting layer, said incisions extend through said liquidretaining and liquid transporting layer, said distributing layer andsaid liquid transporting layer. This embodiment may also be implementedin any of the other exemplary embodiments of wound pads as well.

According to an exemplary embodiment, at least two of said incisionswithin a group of incisions have different depths. It is for exampleconceivable with different combinations of depths according to thedifferent embodiments presented above. It is also conceivable withembodiments in which an incision within a group of incisions extendswholly through a layer and another incision extends only partiallythrough the same layer.

According to an exemplary embodiment, the depth of a first group ofincisions is different from the depth of a second group of incisions.

According to an exemplary embodiment, said wound pad is provided with atleast a first area being provided with said discrete groups ofincisions, and at least one second area which is not provided with saiddiscrete groups of incisions.

According to an exemplary embodiment, said second area that is notprovided with discrete groups of incisions extends along the peripheryof said wound pad. Hence, according to this embodiment, at least an areaextending along the periphery of the wound pad is not provided withgroups of incisions.

According to an exemplary embodiment, the pattern of incisionsthroughout the wound pad is distributed along the periphery of the woundpad. In this embodiment, a central area of the wound pad is not providedwith groups of incisions. Leaving a central area of the wound padwithout any incisions may have a positive effect on the amount of liquidthat may be absorbed by the wound pad, while at the same time anincreased flexibility of the wound pad is provided along its edges. Alsoin this embodiment is it important that the groups of incisions and theincisions within each group are provided in an overlapping manner sothat the wound pad is sufficiently cut. For example, if the wound pad iscut through a layer comprising fibers, the fibers should be cut at leastonce along their extension in the areas where groups of incisions areprovided.

According to an exemplary embodiment, there is provided a wound padhaving a central area that is not provided with groups of incisions, aswell as an area closest to the periphery of the wound pad that is alsonot provided with groups of incisions. Instead, an area there between isprovided with groups of incisions.

According to an exemplary embodiment, the groups of incisions are evenlydistributed over the wound pad. Hence, according to this embodiment, theentire wound pad is provided with groups of incisions. With entire woundpad being provided with groups of incisions is meant to understand thatimaginary tetragons circumscribing the group of incisions, wherein theimaginary tetragons have two sides extending in the machine direction ofthe wound pad and two sides extending in the cross-direction of thewound pad, and wherein each tetragon is the smallest possible tetragoncircumscribing a group of incisions, covers the entire wound pad.

According to an exemplary embodiment, imaginary tetragons circumscribingthe group of incisions, wherein the imaginary tetragons have two sidesextending in the machine direction of the wound pad and two sidesextending in the cross-direction of the wound pad, and wherein eachtetragon is the smallest possible tetragon circumscribing a group ofincisions, covers at least 90% of the wound pad. According to thisembodiment, it is possible with a wound pad which is provided withgroups of incisions over substantially its entire extension. It is thenconceivable that e.g. a small area somewhere on the wound pad, e.g.along its periphery, is not provided with groups of incisions.

According to one exemplary embodiment, a wound pad comprising fibers andbeing provided with a plurality of discrete group of incisions isprovided, wherein each one of said discrete groups of incisionscomprises at least a first and a second incision, wherein said first andsaid second incision extend from a common starting point to a respectiveend point, wherein the end point of said first incision is spaced fromthe end point of said second incision, wherein the common starting pointof a first group of incisions is provided on a first side of animaginary line extending in the machine direction of said fibrous woundpad, and the common starting point of a second group of incisions, beingadjacent to the first group of incisions, is provided on a second sideof said imaginary line, wherein a first incision of said first group ofincisions and a second incision of said second group of incisions eachcross said imaginary line, and wherein the plurality of groups ofincisions are provided such that it is not possible to draw a line fromone side of the wound pad to another in the area between the outermostgroups of incisions, without passing at least one incision.

According to one exemplary embodiment, the wound pad comprises a centralarea being provided with groups of incisions, and a peripheral area thatis not provided with groups of incisions.

According to one exemplary embodiment, the central area covers 75 -95%of the wound pad, and more preferably 85 - 95% of the wound pad.

According to one exemplary embodiment, the peripheral area extends alongthe periphery of the wound pad, and has a width towards the center ofthe wound pad that is in the range of 3 and 12 mm, preferably between 4and 10 mm and most preferably between 4 and 6 mm.

According to one exemplary embodiment, said central area is providedwith a plurality of groups of incisions, such that it is not possible todraw a line through said central area, and in the machine direction ofthe wound pad, without passing at least one incision.

According to one exemplary embodiment, said central area is providedwith a plurality of groups of incisions, such that it is not possible todraw a line through said central area, and in the cross direction of thewound pad, without passing at least one incision.

According to an exemplary embodiment, said central area is provided witha plurality of groups of incisions, such that it is not possible to drawa straight line extending in a diagonal direction of said wound pad,without passing at least one incision.

According to an exemplary embodiment, said central area is provided witha plurality of groups of incisions, such that it is not possible to drawa straight line extending in any direction, from a first peripheralpoint of said wound pad to a second peripheral point of said wound pad,without passing at least one incision.

According to one exemplary embodiment, said central area is providedwith a plurality of groups of incisions, such that it is not possible todraw a line through said central area, and in the machine direction ofthe wound pad, without passing at least three incisions.

According to one exemplary embodiment, said central area is providedwith a plurality of groups of incisions, such that it is not possible todraw a line through said central area, and in the cross direction of thewound pad, without passing at least three incisions.

According to an exemplary embodiment, said central area is provided witha plurality of groups of incisions, such that it is not possible to drawa straight line extending in a diagonal direction of said wound pad,without passing at least five incisions.

According to an exemplary embodiment, said central area is provided witha plurality of groups of incisions, such that it is not possible to drawa straight line extending in any direction, from a first peripheralpoint of said wound pad to a second peripheral point of said wound pad,without passing at least three incisions.

The shape and size of wound pads vary. Therefore, also the number ofgroups of incisions provided on a wound pad varies between differentwound pads. A small wound pad may for example be provided with a few,e.g. three, groups of incisions in the machine direction, and a few,e.g. four, groups of incisions in the cross direction. A rectangularwound pad may of course have more, or even many more, groups ofincisions in one direction, i.e. the machine direction or the crossdirection, than in the other direction. A square-shaped wound pad mayhave approximately the same amount of groups of incisions in bothdirections. A large wound pad may be provided with many more groups ofincisions, in both directions, than a smaller wound pad.

According to an exemplary embodiment, said groups of incisions areprovided in rows of groups of incisions, wherein said rows of discretegroups of incisions are spaced from each other in the cross direction ofthe wound pad.

According to a second aspect of the present invention, a self-adhesivemember for adhering to and covering a portion of a user’s skin isprovided. Said self-adhesive member comprises a wound contact layerhaving a self-adhesive coating and a wound pad according to any one ofthe previous exemplary embodiments attached to said wound contact layer.

The wound pad of the first aspect of the present invention is suitableto use in a self-adhesive member such as a wound dressing.

According to an exemplary embodiment, said wound contact layer comprisesa film layer and an adhesive coating.

According to an exemplary embodiment, said self-adhesive member isprovided such that the wound pad is provided in contact with the filmlayer of said wound contact layer and said adhesive coating of saidwound contact layer is facing towards said user, when the self-adhesivemember is being used.

According to an exemplary embodiment, said liquid transporting layer ofthe wound pad is provided closest to the wound contact layer and theliquid retaining and liquid transporting layer is provided furthest awayfrom the wound contact layer, when a wound pad comprising three layersis used.

According to an exemplary embodiment, said self-adhesive member alsocomprises a backing layer, wherein said backing layer is provided on theopposite side of said wound pad in relation to said wound contact layer.

According to a third aspect of the present invention, a wound padcomprising fibers and being provided with at least a first and a seconddiscrete group of incisions is provided. Each one of said discretegroups of incisions comprises at least a first and a second incision,wherein said first and said second incision extend from a commonstarting point to a respective end point, wherein the end point of saidfirst incision is spaced from the end point of said second incision, andwherein the depth of said first incision within a group of incisions isdifferent from the depth of said second incision within a group ofincisions.

The third aspect of the present invention may be combined with any oneof the different exemplary embodiments disclosed above for the first andsecond aspects of the present invention. The third aspect of the presentinvention may be used together with the first aspect of the presentinvention, but it is not necessary to limit its potential use to woundpads being provided with discrete groups of incisions in which thecommon starting point of said first group of incisions is provided on afirst side of an imaginary line extending in the machine direction ofsaid fibrous wound pad, and the common starting point of said secondgroup of incisions is provided on a second side of said imaginary line,and wherein a first incision of said first group of incisions and asecond incision of said second group of incisions each cross saidimaginary line.

BRIEF DESCRIPTION OF THE DRAWINGS

The above, as well as additional, objects, features and advantages ofthe present invention will be better understood through the followingillustrative and non-limiting detailed description of exemplaryembodiments of the present invention, with reference to the appendeddrawings, wherein:

FIG. 1 illustrates a first embodiment of a wound pad according to thepresent invention forming part of a wound care product, in perspectiveview,

FIG. 2 illustrates the first embodiment of the wound pad according tothe present invention, and a wound care product, in exploded view,

FIG. 3 is a cross-sectional view illustrating a wound care productcomprising a wound pad according to the present invention,

FIG. 4 a is a top view illustrating the pattern of incisions in a woundpad according to the first embodiment of the present invention,

FIG. 4 b is a detailed view of one group of incisions according to thefirst embodiment of the present invention,

FIG. 5 a is a perspective view of an alternative embodiment of thepresent invention,

FIG. 5 b is an exploded view of the alternative embodiment in FIG. 5 a ,

FIGS. 6 a - 6 b are top views illustrating pattern of incisions in awound pad according to alternative embodiments of the present invention,

FIG. 7 is a graph illustrating the improved flexibility in a wound padaccording to the present invention, as compared to prior art products,and

FIGS. 8 a - 8 c illustrates, in perspective views, exemplary embodimentsaccording to a third aspect of the present invention.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

The present invention will now be described more fully hereinafter withreference to the accompanying drawings, in which exemplary embodimentsof the invention are shown. The invention may, however, be embodied inmany different forms and should not be construed as limited to theembodiments set forth herein; rather, these embodiments are provided forthoroughness and completeness, and fully convey the scope of theinvention to the skilled addressee. Like reference characters refer tolike elements throughout the description.

FIGS. 1 and 2 illustrate a first embodiment of the wound pad accordingto the present invention and in an exemplary square-shaped self-adhesivemember 1 for adhering to and covering a portion of a user’s skin, suchas a self-adhesive wound care product. The self-adhesive member 1 is notlimited to have a square shape, it may have any other suitable shape,such as round, oval etc.

The self-adhesive member 1 comprises a backing layer 2 and a woundcontact layer 3 having a self-adhesive coating (not shown), preferably asilicone-gel adhesive coating. The wound contact layer may be eitherunbroken or perforated. The self-adhesive coating of the self-adhesivemember may alternatively be an acrylic or rubber based soft hotmeltcoating.

The backing layer 2 is a flexible layer, which can readily be applied toany part of the wearer’s body. The backing layer is suitably a polymerfilm, preferably a polyurethane film, as such films are suitable forthis purpose. The plastic film, in particular the polyurethane film, mayhave a thickness of less than 100 µm, preferably 10-50 µm, in order toallow the wound care product to adapt closely to the shape of thewearer’s body. The backing layer 2 may alternatively be a laminate,which could suitably include an elastic film made of for examplepolyurethane (PU), ethylene vinyl acetate (EVA) or thermoplasticelastomer (TPE). The laminate could also include a layer of nonwoven ortextile material. The layers of the laminate may be laminated byadhesive lamination, using for example hotmelt or acrylic glue, heatlamination or flame lamination.

A carrier layer (not shown) may also be provided on the backing layer,in order to facilitate handling of the wound care product. The functionof the carrier layer is to support the plastic film and to providesteadiness, while applying the wound care product to the wearer’s skin,whereupon the carrier layer is removed. Such carrier layer may be aplastic film of somewhat higher stiffness than the material used for thebacking layer, or nonwoven material, flexible foam material, or paper,which advantageously is polyethylene-coated, or the like.

The self-adhesive member comprises a central area 6 and an edge area 7comprising an outer edge 8 surrounds the central area 6. At the centralarea 6, a wound pad 4 is provided.

The wound pad 4 comprises in this embodiment three layers, namely aliquid transporting layer 10, a distributing layer 11 and a liquidretaining and liquid transporting layer 12. The liquid transportinglayer 10 is made of foam, such as polyurethane foam, the distributinglayer 11 comprises fibers and is made of a non-woven material, and theliquid retaining and liquid transporting layer 12 is made of a materialcomprising super absorbent material, for example super absorbent fibersor particles. The liquid transporting layer 10 is provided on a firstside of said distributing layer 11, which side is directed towards thewound contact layer 3 when the wound pad is provided to theself-adhesive member 1. The liquid retaining and liquid transportinglayer 12 is provided on the other side of said distributing layer 11 andwill thereby become positioned towards the backing layer 2 when thewound pad 4 is provided to the self-adhesive member 1.

The wound pad 4 is provided with groups 15 of incisions 15 a, 15 b, 15c, which are more clearly seen in FIGS. 4 . As can be seen in FIG. 2 ,the incisions extend in this embodiment through the liquid retaining andliquid transporting layer 12 and the distributing layer 11. The liquidtransporting layer 10 is in this embodiment not provided with anyincisions.

FIG. 3 illustrates the self-adhesive member 1 in FIGS. 1 and 2 incross-section, taken along line III-III in FIG. 1 . As can be seen here,two of the incisions 15 a are illustrated and they cut through thematerial comprising super absorbent material in the liquid retaining andliquid transporting layer 12 and the fiber-based material in thedistributing layer 11. By this, the fibers 14 are cut along theirlength. By cutting through the liquid retaining and liquid transportinglayer and the fibers of the distributing layer, a more flexible productis achieved.

The pattern of incisions on the first exemplary embodiment of a woundpad is illustrated in FIG. 4 a . As can be seen, each group of incisions15 comprises three incisions 15 a, 15 b, 15 c, extending from a commonstarting point 16 in three different directions. The end points 17 a, 17b, 17 c of each one of the incisions 15 a, 15 b, 15 c are distanced fromeach other. This is also illustrated in enlarged view in FIG. 4 b .

In the illustrated embodiment, the first incision 15 a in each group ofincisions extends in the cross-direction CD of the wound pad, i.e.perpendicular to the machine direction MD of the wound pad. The twoother incisions 15 b, 15 c of each group of incisions are provided withan angle to the machine direction MD of the wound pad. The angles α, β,γ between each one of the three incisions is in this embodiment thesame, namely 120°. The lengths L1, L2 and L3 of the respective incisionsin this embodiment is also the same for all three incisions within onegroup of incisions.

The groups of incisions 15 are provided in a pattern in which oneincision of a group of incisions 15 overlap at least one incision ofanother group of incisions. In other words, the common starting point 16of the first group of incisions 15 is provided on a first side of animaginary line 20 extending in the machine direction of said fibrouswound pad, and the common starting point 16 of the second group ofincisions 15 is provided on a second side of said imaginary line 20, andwherein a first incision 15 a of said first group of incisions and asecond incision 15 b of said second group of incisions each cross saidimaginary line. In the illustrated embodiment, also a third incision 15c of the second group of incisions cross said imaginary line. By this,it is not possible to draw a straight line from any point of theperiphery of the wound pad 4 to another point at the periphery of thewound pad 4, in the areas where groups of incisions are provided and inthe machine direction of the wound pad, without passing through at leastone incision. Hence, the wound pad is cut on many instances, and forexample, the fibres of the distributing layer 11 are cut at least onceduring their extension.

As can be seen in the drawings, a narrow area extending along theperiphery of the wound pad has been left without groups of incisions,and in that area the wound pad may not be cut. However, that areaconstitutes only a minor portion of the total area of the wound pad, andleaving such an area without incisions does not compromise the positiveeffects of the present invention. Furthermore, by leaving an areaclosest to the periphery without incisions reduces the risk that minorportions of the outermost part of the wound pad will fall off from thewound pad.

In the pattern shown in FIGS. 4 , each one of the groups of incisions 15chosen in one of the rows are overlapped by four other groups ofincisions 115, 215, 315, 415. The features of the groups of incisions115, 215, 315 and 415 are the same as for any one of the other groups15. They have only been denoted differently to illustrate that they inthis example are the ones overlapping one of the other groups 15 ofincisions. In FIGS. 5 a and 5 b , an alternative embodiment isillustrated. However, most features in this embodiment are similar tothe embodiment described in relation to FIGS. 1 -4 b , and thesefeatures will not be elucidated again for this embodiment. Thedifference between this embodiment and the previous one is that in thisembodiment, only a portion close to the periphery of the wound pad isprovided with groups 15 of incisions. However, also in this embodimentis the outermost portion, i.e. the portion adjacent to the periphery ofthe wound pad, not provided with incisions.

However, the pattern of incisions are also for this embodiment providedsuch that at least one incision 15 a, 15 b, 15 c within a group 15 ofincisions overlap an incision 15 a, 15 b, 15 c of another group 15 ofincisions, such that it becomes impossible to draw a straight line fromany point of the periphery of the wound pad 4 to another point at theperiphery of the wound pad 4, at least not in the machine direction ofthe wound pad and except for the outermost portion of the wound pad,without passing through at least one incision. Hence, also in thisembodiment is the wound pad cut through a sufficient degree, and forexample, most of the fibres of the distributing layer 11 are cut atleast once during their extension.

FIGS. 6 a and 6 b illustrate different alternative embodiments of thedesign of the incisions within the groups of incisions. In FIG. 6 a afirst alternative embodiment of the group 515 of incisions is shown,which comprises four incisions 515 a - d, extending from a common centrepoint 516. In this embodiment, the angles between each one of theincisions are perpendicular. In FIG. 6 b , a second alternativeembodiment is shown. In this embodiment of the group 615 of incisionseach group comprises five incisions 615 a - e, extending from a commoncentre point 616. Also in this embodiment are the angles between eachone of the incisions similar to each other, namely 72°. The pattern ofincisions are also for these embodiments provided such that at least oneincision within a group of incisions overlap an incision of anothergroup of incisions, and the same effect as for the previously describedembodiments are achieved. Features and variations not mentionedspecifically for these two alternative embodiments are the same as forthe first embodiment.

The incisions may be produced by known measures such as cutting with amechanical tool, e.g. a knife, or with e.g. laser. Such methods areknown in the art and will not be further elaborated upon herein.

FIG. 7 discloses an illustrative graph of the flexibility of a wound padaccording to the present invention compared with prior art wound pads.In these tests, the test method ASTM D882-02 was used but modifiedregarding resolution, i.e. additional measurements were included.Thewound pad tested in this test comprised two nonwoven layers, one withpolyacrylate, cotton and polyester, and one with polyester andviscose.The line denoted “Reference” illustrates a wound pad withoutincisions. As can be seen, a large force is required to strain the woundpad. When the product has been strained approximately 20 - 25%, it willbreak and therefore less force is required for the final straining up to30%. The line denoted 21 illustrates a wound pad provided with incisionsthat are not overlapping each other. The characteristics of this woundpad during stretching are the same as for the wound pad withoutincisions, even if less force is required. The line denoted 20illustrates a wound pad according to the present invention and as can beseen, less force is required for straining and the wound pad can bestretched to a larger degree without breaking. The line denoted 22illustrates another embodiment within the scope of the presentinvention, although it is not as preferred as the embodiment denoted 20.Less incisions are provided in the embodiment denoted 22 than in theembodiment denoted 20 and as can be seen in the graph, more force isrequired to strain the embodiment denoted 22. However, as is also seenin the graph, it requires less force to strain the embodiment denoted 22than the wound pads not falling within the scope of the presentinvention, and the embodiment denoted 22 does also not break when it hasbeen strained to 20 - 25%.

The present inventors have also made a comparative analysis of the totalfluid handling capacity of a dressing being provided with a wound padaccording to the present invention, as compared with a dressing beingprovided with a wound pad according to prior art. The fluid handlingcapacity of the dressings was measured according to EN 13726-1: 2002(E), 3.3. Fluid handling capacity (modified regarding the amount of TestSolution A; i.e. 30 ml was used). The dressings had the exact sameconstruction with regard to backing layer, wound pad, and wound contactlayer; with the difference that the distribution layer of the wound padof the inventive dressing was provided with incisions according to thepresent invention. The groups of incisions were similar to those denoted20 in FIG. 7 . No incisions were provided in the distribution layer ofthe prior art dressing. The total fluid handling capacity was increasedabout 20%, and the moisture vapour loss, MVL, was increased by 39% withthe inventive dressing. This can be attributed to the increased productflexibility provided by the incisions. The wound pad is allowed tostretch in all directions during wet conditions. Therefore, the movementand spreading of liquid within the dressing is improved, and excessliquid can evaporate from the product, and be transferred out from thewound pad through the backing layer. In other words, the dressing doesnot become saturated as quickly, and the dressing can be left in placefor a longer time compared to a non-flexible product according to theprior art.

FIGS. 8 a - 8 c illustrate another aspect of the present invention in aschematic manner. Same reference numerals as those previously usedrepresent the same features and will not be further elaborated upon. Inthis aspect, a group of incisions 815 is illustrated. The group ofincisions consists of three incisions 815 a, 815 b and 815 c, but thisaspect is conceivable to combine with any one of the differentembodiments of incisions described for the different embodiments above.As can be seen in FIG. 8 a , the depth of the first incision 815 a issmaller than the depth of the second and third incisions 815 b and 815c. It is for example possible that the first incision 815 a extendsthrough one layer of the wound pad and that the second and thirdincisions 815 b and 815 c extend through more than one layer. This ise.g. illustrated in FIG. 8 b in which all three incisions extend throughthe liquid retaining and liquid transporting layer and only the secondand third incisions extend through the distributing layer 11. It is alsoconceivable that they extend to different depths within a layer of thewound pad.

FIG. 8 c illustrates another embodiment within this inventive aspect. Inthis embodiment, the incisions are made from the liquid transportinglayer 10 side of the wound pad. All three incisions 815 a, 815 b and 815c extend through the liquid transporting layer 10. However, the depthsof the incisions vary and only two incisions within each group ofincisions extend through the distributing layer 11. In this embodiment,the depths of the incisions vary between different groups of incisions,and as can be seen, in one group it is the first incision 815 a that hasthe smallest depth, while it in another group is the second incision 815b and in yet another group it is the third incision 815 c that has thesmallest depth.

Although exemplary embodiments of the present invention have beendescribed herein, it should be apparent to those having ordinary skillin the art that a number of changes, modifications or alterations to theinvention described herein may be made. Thus, the above description ofthe various embodiments and aspects of the present invention and theaccompanying drawings are to be regarded as non-limiting examples of theinvention and the scope of protection is defined by the appended claims.

For example, even though the wound pad according to the presentinvention in the foregoing description has been described as formingpart of a self-adhesive member is it conceivable that the wound pad maybe sold and distributed as a stand-alone product. It is also conceivablethat the wound pad may be used in other applications than wound careproducts.

The angle between each one of the three incisions has been described asbeing the same. It is however conceivable that it is not the samebetween each one of the incisions. The length of the incisions have alsobeen described as being the same for all three incisions within onegroup of incisions. It is however also conceivable that incisions ofdifferent lenghts are provided, either within a group of incisions or indifferent groups of incisions.

The incisions have in many embodiments been described as being cut fromthe liquid retaining and liquid transporting layer side of the wound padand through the liquid retaining and liquid transporting layer and thedistributing layer. It is however also conceivable that the incisionsare made from the other side of the wound pad, i.e. the cuts are madethrough the liquid transporting layer and the distributing layer. It isalso conceivable with wound pads in which the cut is made through theentire wound pad, i.e. through all three layers of the embodimentdescribed above. Even further, it is also concievable with embodimentsin which one layer is partially cut through. For example, if theincisions are made from the liquid retaining and liquid transportinglayer side of the wound pad, then the incisions may have such anextension in the depth direction of the wound that the liquid retainingand liquid transporting layer and distributing layer are cut through,while the incision extends only partially into the liquid transportinglayer. The same also applies if the cut is made from the liquidtransporting layer side of the wound pad; the cut may then insteadextend partially into the liquid retaining and liquid transportinglayer.

Furthermore, the wound pad has been described as comprising an liquidtransporting layer, a distributing layer and a liquid retaining andliquid transporting layer. It is however also conceivable withembodiments in which a wound pad comprises a liquid retaining and liquidtransporting layer and a distributing layer, but no liquid transportinglayer. In such an embodiment, the distributing layer would be closest tothe wound contact layer when the wound pad is provided to aself-adhesive member. Another exemplary embodiment of a wound padcomprises a layer of compressed foam and a distributing layer. A yetfurther exemplary embodiment is similar to the one presented above inrelation to FIGS. 1 - 5 and 8 , but with an additional layer comprisingfoam adjacent the side of the liquid retaining and liquid transportinglayer not being in contact with the distributing layer.

A person skilled in the art also realizes that the different alternativeembodiments and aspects mentioned above may be combined with each otherin various suitable embodiments within the scope of the claims, e.g.with regard to the number of layers and their constitution, the designand shape of the group of incisions, the positioning of the groups ofincisions and the depth of the group of incisions.

Furthermore, any reference signs in the claims should not be construedas limiting the scope.

1-15. (canceled)
 16. A wound pad comprising: a) a liquid retaininglayer, and b) a distributing layer, wherein the liquid retaining layer,or the distributing layer, or both the liquid retaining layer and thedistributing layer comprises fibers and being provided with at least afirst and a second discrete group of incisions, wherein the first andsecond discrete groups of incisions each comprises a first incisionextending from a starting point to a respective end point, and whereinthe first incision extends though the liquid retaining layer, or thedistributing layer, or both the liquid retaining layer and thedistributing layer.
 17. The wound pad of claim 16, wherein thedistributing layer comprises the fibers and being provided with the atleast the first and a second discrete group of incisions, and whereinthe first incision extends though the distributing layer.
 18. The woundpad of claim 16, wherein the liquid retaining layer comprises the fibersand being provided with the at least the first and a second discretegroup of incisions, and wherein the first incision extends though theliquid retaining layer.
 19. The wound pad of claim 16, wherein theliquid retaining layer and the distributing layer comprise the fibersand being provided with the at least the first and a second discretegroup of incisions, and wherein the at least first incision extendsthough the liquid retaining layer and the distributing layer.
 20. Thewound pad of claim 16, wherein the first and second discrete groups ofincisions further comprise a second incision extending from the startingpoint of the first incision to a respective end point, and wherein therespective end point of the first incision is spaced from the respectiveend point of the second incision.
 21. The wound pad of claim 20, whereinthe first and second discrete groups of incisions further comprise athird incision extending from the starting point of the first and secondincisions to a respective end point, wherein the respective end point ofthe first incision is spaced from the respective end points of thesecond and third incisions, and wherein the respective end point of thesecond incision is spaced from the respective end points of the firstand third incisions.
 22. The wound pad of claim 21, wherein in the firstand second discrete group of incisions: a) the first incision ispositioned to have an angle between 60° and 150° in a clockwisedirection relative to a position of the second incision; b) the secondincision is positioned to have an angle between 60° and 150° in aclockwise direction relative to a position of the third incision; and c)the third incision is positioned to have an angle between 60° and 150°in a clockwise direction relative to a position of the first incision.23. The wound pad of claim 22, wherein: a) the first incision ispositioned to have an angle of 120° in a clockwise direction relative toa position of the second incision; b) the second incision is positionedto have an angle of 120° in a clockwise direction relative to a positionof the third incision; and c) the third incision is positioned to havean angle of 120° in a clockwise direction relative to a position of thefirst incision.
 24. The wound pad of claim 21, wherein the firstincision, the second incision, and third incision all have an identicallength.
 25. The wound pad of claim 16, wherein the wound pad furthercomprises a liquid transporting layer, wherein the distributing layercomprises a first side and an opposing second side, and wherein theliquid transporting layer is arranged on the first side of thedistributing layer and the liquid retaining layer is arranged on theopposing second side of the distributing layer.
 26. The wound pad ofclaim 25, wherein the liquid transporting layer comprises a foam basedmaterial.
 27. The wound pad of claim 26, wherein the foam based materialis a polyurethane foam.
 28. The wound pad of claim 16, wherein the firstdiscrete group of incisions has a dimension and a shape that isidentical to a dimension and a shape of the second discrete group ofincisions provided on the wound pad.
 29. The wound pad of claim 16,wherein the distributing layer comprises a nonwoven material.
 30. Thewound pad of claim 16, wherein the liquid retaining layer comprises asuper absorbent material.
 31. The wound pad of claim 30, wherein thesuper absorbent material comprises a super absorbent fiber.
 32. Thewound pad of claim 31, wherein the liquid retaining layer comprises thefibers and being provided with at least the first and the seconddiscrete group of incisions.
 33. The wound pad of claim 16, wherein thewound pad has a machine direction and a cross direction, and wherein thefirst incision extends in a direction that is not parallel to themachine direction.
 34. The wound pad of claim 16, wherein the wound padhas a machine direction and a cross direction, and wherein the firstincision extends the cross direction.
 35. A self-adhesive member foradhering to and covering a portion of a user’s skin, the self-adhesivemember comprising a wound contact layer having a self-adhesive coatingand the wound pad of claim 16 attached to the wound contact layer.